Study of Primary Fascial Closure Rate in Patients With Open Abdomen Treated With Abthera Versus Barker Technique

This study is being done to compare two different Temporary Abdominal Closure methods that could be used in cases of open abdomen. The methods being compared are the Barker's vacuum packing technique (BVPT) and the Open Abdomen Negative Pressure Therapy System (ABThera). The BVPT will be made up by an internal plastic layer to cover abdominal viscera, a second layer with surgical sponges and a suction drain and will be covered by an adhesive plastic layer. Then the dressing will be connected to the hospital's vacuum system. The ABThera dressing is available commercially.

Study Participants Enrollment will happen at the operating room

Investigator will include in this study patients who have the following indications to laparostomy:

• Damage control surgery in trauma patients,
• Patients with abdominal compartment syndrome,
• Septic shock patients requiring short surgery and inability to close the abdominal cavity.

Signing the consent form will be held in order of preference by:

1. Patient
2. Legal representative
3. Doctor appointed by the hospital that does not participate in the study(only in cases where the urgency of the surgery do not allow contact with the representatives). In the latter case the signature of the term should be applied to the legal representative as soon as possible. Criteria for inclusion and exclusion: Inclusion:

• Patients with indication of an open abdomen According to the Attending physician (above criteria) Exclusion:
• Pregnancy;
• Chronic renal impairment,
• Child-Pugh C,
• Body index over 40 kg / m2,
• Uncontrolled bleeding during laparotomy
• Patients progressing to death within the first 48 hours Allocation Concealment and Randomization Randomization will be performed by central online dedicated site in the ratio of 1: 1. When a patient is eligible, a surgeon will access the Web site, enter patient's information to know the assigned allocation. Variable block size randomization will be utilized stratified by study center Assuming a closure rate of 75% in the Abthera arm and 35% in the Control arm, a study with 36 patients in each treatment arm (72 total) would have 90% power to detect such a difference at the 0.05 significance level. In order to evaluate closure for 36 patients in each arm, with an estimated loss of 30% either by withdraw or death prior to 48h. So the study will enroll 94 patients (47 in each treatment group) After surgery, patients will be referred to the intensive care unit (ICU). In patients' Barker Group a fenestrated plastic will be used and that will be in contact with viscera followed by four pads with a suction drain and an adhesive finishing layer. In ABThera group technique the dressing will be done according to the description and the manufacturer's instructions (Acelity, San Antonio, TX). Primary Objective :
• Fascial closure in 30 days Secondary objectives
• Demographic variables (gender, age, comorbidities, mechanism of injury or disease),
• Indication of laparostomy,
• Systolic blood pressure,
• Amount of fluid drained by the healing of laparostomy,
• Amount of crystalloid,
• Amount of hemoconcentrated,
• APACHE II ICU admission,
• Length of stay in the ICU,
• Length of mechanical ventilation,
• Length of hospital stay,
• Time to closure
• Adverse Events
• Complications
• Mortality. In trauma patients the score Revised Trauma (RTS) and the Injury Severity Score (ISS) will be calculated Statistical analysis Descriptive variables will be summarized as frequencies and percentages. Continuous variable data will be presented as means and standard deviations or medians and ranges, depending on the distribution. The analysis of the qualitative variables will be done through measures of association (chi-square or Fisher 's exact test). The analysis of quantitative variables will be made by means of different tests (parametric and nonparametric) depending on the outcome of the applied normality test